/type1 { dup == type == clear } def

true type1
false type1
null type1
2 type1
(abc) type1
/name type1
/add load type1
mark type1
[ 1 2 3 ] type1
<< /a 1 >> type1
{ add } type1

(xyz) cvn ==

(abc) 0 string cvs ==
/efg 0 string cvs ==
true 0 string cvs ==
false 0 string cvs ==
99 0 string cvs ==
-309 0 string cvs ==
null 0 string cvs ==
[ ] 0 string cvs ==
<< >> 0 string cvs ==
{ } 0 string cvs ==

1 cvx 2 cvx [ /add cvx ] cvx exec ==

{ /abc dup cvx pstack eq == } exec
{ [  ] dup cvx pstack eq == } exec
